SOLUTION: The average score of 100 students taking a statistics final was 70 with a standard deviation of 7. Assuming a normal distribution, what is the probability that a student scored 90

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Question 830972: The average score of 100 students taking a statistics final was 70 with a standard deviation of 7. Assuming a normal distribution, what is the probability that a student scored 90 or higher
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Find the z score.
z=%28x-m%29%2Fs=%2890-70%29%2F7=2.857
P%282.857%29=0.997863
So 99.7863% of students scored 90 or less, leaving
P(>90)=1-0.997863
P(>90)=0.002137